- Iron(0) nanoparticles mediated direct conversion of aryl/heteroaryl amines to chalcogenides via in situ diazotization
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A simple procedure for the synthesis of organo-chalcogenides has been developed by the reaction of aryl/heteroaryl amines with di-aryl/heteroaryl dichalcogenides in the presence of tBuONO and Fe(0) nanoparticles. The reaction proceeds via in situ diazotization followed by chalcogenation. A series of functionalized diaryl/aryl heteroaryl/diheteroaryl/aryl-alkyl selenides, sulfides and tellurides have been obtained by this procedure. Significantly, using this procedure 2,4-dinitroaniline is converted to (2,4-dinitrophenyl)(phenyl)selane which is known as thioredoxin reductase (TR) and glutathione reductase (GR) inhibitor. The reaction goes by a radical pathway and a plausible mechanism has been suggested.
- Panja, Subir,Maity, Pintu,Kundu, Debasish,Ranu, Brindaban C.
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supporting information
p. 3441 - 3445
(2017/08/10)
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- Visible light photocatalyzed direct conversion of aryl-/heteroarylamines to selenides at room temperature
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A novel strategy for the direct conversion of aryl- and heteroarylamines to selenides has been developed via diazotization of amines with tert-butyl nitrite in neutral medium followed by reaction with diaryl/diheteroaryl/dialkyl diselenides in one pot under photocatalysis at room temperature in the absence of any metal. This reaction is also applied for the synthesis of tellurides. The selenylation of heteroarylamine by this protocol is of much significance because of the difficulty in diazotization of these molecules by a standard diazotization method in acid medium.
- Kundu, Debasish,Ahammed, Sabir,Ranu, Brindaban C.
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supporting information
p. 1814 - 1817
(2014/04/17)
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- Solvent-controlled halo-selective selenylation of aryl halides catalyzed by Cu(II) supported on Al2O3. A general protocol for the synthesis of unsymmetrical organo mono- and bis-selenides
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Alumina-supported Cu(II) efficiently catalyzes selenylation of aryl iodides and aryl bromides by diaryl, dialkyl, and diheteroaryl diselenides in water and PEG-600, respectively, leading to a general route toward synthesis of unsymmetrical diaryl, aryl-alkyl, aryl-heteroaryl, and diheteroaryl selenides. A sequential reaction of bromoiodobenzene with one diaryl/diheteroaryl/dialkyl diselenide in water and another diaryl/diheteroaryl/dialkyl diselenide in PEG-600 in the second step produces unsymmetrical diaryl, diheteroaryl, or aryl-alkyl bis-selanyl benzene. A library of functionalized organo mono- and bis-selenides, including a potent biologically active molecule and a couple of analogues of bioactive selenides, were obtained in high yields by this protocol. The reactions are chemoselective and high yielding. The Cu-Al2O 3 catalyst is recycled for seven runs without any appreciable loss of activity.
- Chatterjee, Tanmay,Ranu, Brindaban C.
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p. 7145 - 7153
(2013/08/23)
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- Synthesis of azido arylselenides and azido aryldiselenides: a new class of selenium-nitrogen compounds
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We present here our results of the efficient synthesis of azido arylselenides and azido aryldiselenides under mild conditions. Starting from nitrogen-substituted benzenes, we incorporated selenium atom at aromatic ring and obtained amino arylselenides and diselenides in satisfactory yields. Treatment of these compounds with iso-pentyl nitrite (i-C5H11ONO) and azido trimethylsilane (Me3SiN3) in THF affords a variety of azido arylselenides and diselenides in good to excellent yields.
- Deobald, Anna Maria,Simon de Camargo, Leandro R.,Tabarelli, Greice,H?rner, Manfredo,Rodrigues, Oscar E.D.,Alves, Diego,Braga, Ant?nio L.
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experimental part
p. 3364 - 3367
(2010/08/19)
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- Preparation of the first bench-stable phenyl selenolate: An interesting "on water" nucleophilic reagent
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In this communication we report the synthesis and the characterization of the first solid and air-stable selenolates, starting from commercially available phenylselenenyl halides and elemental zinc. These reagents were efficiently employed in the ring ope
- Santi, Claudio,Santoro, Stefano,Battistelli, Benedetta,Testaferri, Lorenzo,Tiecco, Marcello
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scheme or table
p. 5387 - 5390
(2009/05/07)
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- Evidence for a common selenolate intermediate in the glutathione peroxidase-like catalysis of α-(phenylselenenyl) ketones and diphenyl diselenide
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The glutathione peroxidase-like catalysis of α-(phenylselenenyl) ketones was investigated. Degradation studies demonstrated the rapid cleavage of the aliphatic carbon-selenium bond of α-(phenylselenenyl) ketones by glutathione at pH 6.9 in a methanolic phosphate buffer under argon. On treatment with excess glutathione under aerobic conditions, α-(phenylselenenyl) ketones, S- (phenylselenenyl)glutathione and diphenyl diselenide were all shown to give benzeneselenolate. This material was found to be oxidized by hydrogen peroxide considerably faster than α-(phenylselenenyl) ketones, S- (phenylselenenyl)glutathione or diphenyl diselenide. A catalytic mechanism involving benzeneselenolate, benzeneselenenic acid and S- (phenylselenenyl)glutathione as crucial intermediates was proposed to account for the glutathione peroxidase-like catalysis of α-(phenylselenenyl) ketones and diphenyl diselenide.
- Engman, Lars,Andersson, Claes,Morgenstern, Ralf,Cotgreave, Ian A.,Andersson, Carl-Magnus,Hallberg, Anders
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p. 2929 - 2938
(2007/10/02)
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- Thiol/Diselenide Exchange for the Generation of Benzeneselenolate Ion. Catalytic Reductive Ring-Opening of α,β-Epoxy Ketones
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In the presence of N-acetylcysteine sodium salt, benzeneselenolate ion was generated in situ from diphenyl diselenide via thiol/diselenide and thiol/selenenyl sulfide exchange in aqueous methanol under mild conditions.Benzeneselenolate ion thus formed was efficiently alkylated and arylated to afford alkyl phenyl selenides and aryl phenyl selenides, respectively. α,β-Epoxy ketones were catalytically reduced by benzeneselenolate ion to afford β-hydroxy ketones (aldols) in good yields.The stereospecificity of the reaction was demonstrated in the preparation of optically active β-hydroxy ketones from chiral α,β-epoxy ketones.
- Engman, Lars,Stern, David
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p. 5179 - 5183
(2007/10/02)
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- The use of aminoiminomethanesulfinic acid (thiourea dioxide) under phase transfer conditions for generating organochalcogenate anions. Synthesis of sulfides, selenides and tellurides
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A procedure is described which allows for the in situ synthesis of arylalkyl, diaryl and dialkylchalcogenides under phase transfer conditions starting from the corresponding diorganodichalcogenides.The dichalcogenides are reduced by aminoiminomethanesulfinic acid (thiourea dioxide) in alkaline medium and catalyzed by a quaternary ammonium salt.The reduction proceeds easily for diaryl disulfides and diaryl diselenides at a sodium hydroxide concentration of 13percent; diaryl ditellurides require a 50percent sodium hydroxide solution to give the aryl tellurolate anion.The dialkyl diselenides and dialkyl ditellurides are more difficult to reduce.The intermediate arylthiolates and arylselenolates are quenched by alkyl and activated aryl halides to give the corresponding sulfides and selenides in high yield (77-97percent).The aryltellurolates react with alkyl halides giving the aryl alkyl tellurides in 81-96percent yield.The procedure could not be successfully used for the synthesis of dialkylselenides and dialkyl tellurides; low yields and mixture of products were formed.
- Comasseto, J. V.,Lang, E. S.,Ferreira, J. Tercio B.,Simonelli, F.,Correira, V. R.
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p. 329 - 340
(2007/10/02)
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- SYNTHESIS OF DIARYLSELENIDES AND DIARYLSULFIDES UNDER PHASE TRANSFER CONDITIONS
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Diarylselenides and diarylsulfides are synthesized from the corresponding diaryldiselenide and diaryldisulfide by reduction with aminoiminomehanesulfinic acid, and reaction with activated aryl halides under phase transfer conditions.The reactions yields vary from good to excellent.
- Ferreira, J. Tercio,Simonelli, F.,Comasseto, J. V.
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p. 1335 - 1342
(2007/10/02)
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- Oxidation of Hydrazines with Benzeneseleninic Acid and Anhydride
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Benzeneseleninic acid (1) and anhydride (2) oxidize hydrazine or 1,2-disubstituted derivatives to corresponding diazenes.Hydrazides afford selenoesters 4, N,N'-diacyl- or diaroylhydrazines 5, and carboxylic acids.Benzeneselenenic acid (7) is a required intermediate in selenoester formation and may be generated independently by the reaction of triphenylphosphine with 1.Selenoesters are efficiently prepared by the slow addition of a mixture of the hydrazide and triphenylphosphine to 1 in dichloromethane solution.Polar solvents are unsuitable.Inverse addition provides compounds 5 as major products.Oxidation of hydrazides of structure HO-(CH2)nCONHNH2 gives the corresponding selenoesters 14 and acids 16 when n=11 or 14 lactones 17 and 18 when n=4 or 3.Arylhydrazines react with 1 or 2 to furnish arenes 23 and aryl phenyl selenides 24.
- Back, Thomas G.,Collins, Scott,Ker, Russell G.
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p. 1564 - 1570
(2007/10/02)
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